Note: Javascript is disabled or is not supported by your browser. For this reason, some items on this page will be unavailable. For more information about this message, please visit this page: About CDC.gov.

We believe that industrial hygienists and allied professionals consider OELs to be one of the most effective tools for performing risk assessments upon which risk management strategies for worker protection can be based. We may never have OELs for all chemical hazards; however, it is critical that we accelerate the establishment of credible and respected OELs to provide a basis for protecting workers. The first step in this large task may be to come to some agreement on a unitary scientific approach to assessing hazards and applying hazard assessments to the setting of OELs. However, many impediments exist to this seemingly obvious solution, including legal, regulatory, economic, political and cultural issues and other factors outside of the usual scientific arguments on health effects. These difficulties have stalled development of OELs in the U.S. and, seemingly, the rest of the world. OELs that have been developed outside of the regulatory system as guidance have been subject to significant litigation. At our present rate of progress, it is extremely unlikely that significant numbers of new OELs will be developed. Litigation could further reduce, restrict or eliminate the efforts of organizations like ACGIH to generate new OELs. Many in our profession consider this possibility unacceptable. So, how can we revive the OEL-setting process in a way that benefits all parties? In Europe, REACH requires the development of DNELs. However, these values will not be consensus recommendations - they will be determined by the manufacturer or supplier of the material. Small manufacturers will not have the resources to do exhaustive studies, and the level of scientific review of the DNELs, once submitted, is unclear. How effective this system will be in protecting workers remains to be seen. Control banding may be an alternative approach to OELs. In theory, a well executed process, guided by professionals who appreciate the science of toxicology, can set hazard bands for materials that lack adequate toxicity and hazard data needed for a formal OEL. However, the theory has not been adequately tested to see if indeed the process is protective. The specificity and sensitivity of control banding has been only minimally validated, and the preliminary results have not been impressive. Some governments around the world are still establishing OELs. These values are not generally applied outside of the host country and may include many more considerations than just health effects. Additionally, actual measurements for ambient air levels of the OEL substances are rarely performed except in a few countries. This suggests that the traditional use of OELs is not widely practiced worldwide. In closing, we believe that OELs are absolutely critical! We hope that this paper will encourage stakeholders worldwide to discuss the critical issues, continue the dialogue and help determine the future for OELs. By working together, our profession can, with others, forge a way forward.